Apparatus comprising perkins tubes



J FLAIC;

APPARATUS COMPRISING PERKINS TUBES Flled Jan 26 1923 April 2O 1926.

/7 TToR/VE VS Patented Apr. 20, 1926. v

UNITED STATES 1,581,114 PATENT oFFlcE.

.APPARATUS GOMPRIYSINGl PERKINS TUBES.

Application led January 26, 1923. Serial No. 615,109.

To all 'whom t may cof/wem.'

Be it known that I, JAcoBUs HAAG, a subject of the Queen of the Netherlands, reslding at Amsterdam, Netherlands, have invented certain new and useful Improvements in Apparatus `Comprising Perkins Tubes, of which the following is a speclcation.

The object omy present invention 1s to provide an improved construction of appa- -ratus for the generation of steam or pressure vapor which employs `Perkins tubes, suchas is disclosed in the Perkins United States Patent No. 529,304, comprising hermetically closed tubes partly filled with suitable liquld and adapted, when heated at one end, to emit heat at the other end. The annexed drawing shows apparatus of this type with an embodiment of my present invention.

On the drawing, Figure l shows somewhat diagrammatically af' vertical section of a steam boilerv provided with Perkins tubes, whereas 4Figure 2 shows on an enlarged scale a vertical section of the upper portlon of a Perkins tube closed by means of a screwthreaded plug. As a matter of course the invention may also be embodied in ovens, furnaces and any other apparatus in which Perkins tubes are used to heat an enclosed space.

In Figure 1, A is the furnace, B is the boiler to which heat produced in A is to be transmitted. y

In accordance -vwith my presentinvention, the Perkins tube 4 passes tightly both through the top plate 3 and. through the bottom plate 7 of the boiler, and the top end of the tube is hermetically closed by means of a screw-threaded cap 8 screwed on male thread 9, of thetube. This cap could be replaced with equal advantage by a screwthreaded plu adapted to be receivedv by female threa in the tube; Perfectly tight joints between the tube 4 and the plates 3 and 7 are obtained by expanding the tube at these junctures.

By expanding the tubes in accordance with Imy present invention I am enabled to support the tubes in fluid tight engagement with the container walls without necessitating the use of` conical or other enlargements'on the tubes, or the provision of enlarged holes in the tube plates. such as characterize the prior art constructions. As a result I can employ straight drawn tubing for making thetubes, thus not only simpliying the construction and the cost of manu-l facture of 'the tubes as well as *theI tube sheets, but also the installation of the tubes. Furthermore, by avoiding the .use ofy enlarged holes in the tube sheets or'container walls, lweakening ofbthe walls is obviat'ed, therefore more tubes ma be installed vin for a given area of container wall and the heating capacity of the apparatus greatly (increased. After the expansion ofthe tubes,-

the apparatus may be water tested, and the Perkins tubes may then be filled and closed. These operations are effected outside the boiler, so that they do not offer any diculty. Moreover, in the event of leakage' occurring between a tube and a boiler plate, repair may be effected even `whilst the boiler `1s 1n use, lnasmuch as access may be obtained to the interior of the tube b removing the closure 8 and a tube expander inserted for the purpose of expanding the wall of the tube at the. point of leakage through the boiler wall 3 or 7. During this operation the tube may be cooled by water admitted thereinto. As will be understood the top end of the tube 4 should extend suttciently far .beyond the top plate 3 to avoid injury, during'the operation of expansion, to the `screw-thread provided for the reception of the cap or the plug, as shown.

My novel construction also permit -of checking the operation of the tubes. or instance, I may providev the screw-cap or screw plug of the tube with` a small pipe closed at its bottom end and adapted to receive a thermometer. By thisimeans, I am enabled to check the operation of each tube separately and obtain the maximum efficiency of the apparatus. This construction is illustrated in Figure 2. The o en end of tube 4 is here closed by a screw plug 10 having a central hole for receiving a small pipev 11, the closed bottom. end of which protrudesv into the vapour space 'of tube 4. This pipe serves to receive a thermometer 12. v

What 'Ilclaim is:

1. Apparatus forpthe indirect generation of steam by the use of hermetically sealed tubes which are partially filled with a li uid and which traverse a heating cham l r, ycharacterized by the ends of said tubes projecting beyond the walls of said chamber, one of said projecting ends of each tube being open, the walls of said tube being expanded into contact-with the walls of said chamber to form therewith a steam tight joint, and' a removable closure for hermetioally sealing said projecting open end.

2. Apparatus for the indirect generation of steam by the use of hermetically sealed tubes which are partially filled with a liquid and which traverse a `heating chamber, characterized by the ends of said tubes projecting beyond the walls of said heating chamber, one of the projecting ends of each tube being open and provided with screw threads, a removable closure to engage with said screw threads and hermetically seal said open end of said tube, the walls of saidvtubes being expanded into contact with the walls of said chamber to form therewith a steam tight joint, and the screw threaded ends of said tubes projecting beyond the expanded portions thereof a suicient distance to prevent distortion of. the screw threads by the 20 expansion of said tubes.

In testimony whereof I aix my signature.

JACOBUS: HAAG. 

